This invention relates to circuitry for use in a cartridge type tape player for operating the player in a two or a four channel mode.
Standard cartridge tape players comprise eight tracks recorded thereon. A cartridge of four channel program material contains two programs each having four recorded tracks whereas a two channel cartridge contains four programs, each program having two recorded tracks. Indexing means have been developed adapting the player to either two channel or four channel cartridges as well as accomplishing variable program selection. Conventional systems achieve indexing by mechanically moving the tape head with respect to the magnetic tape. Typically, a solenoid plunger rotates a cam which in turn relocates the tape head. As proper player operation requires exacting alignment of the tape head pickups with the recorded tracks on the tape, the mechanical system must maintain close tolerances.
The mechanical indexing system requires several costly mechanical parts, it requires close tolerances, and it is subject to wear degradation.
Due to recent technological advances in electronic circuit integration, it is becoming increasingly more feasible to replace mechanical switches with fully electronic switches. The electronic switches are more reliable and consume less space. Moreover, where a multiplicity of switches are required, the cost per electronic switch can be considerably reduced as a result of fabricating several switches in a single integrated circuit.